Inhaler and replaceable liquid reservoir for an inhaler

ABSTRACT

Inhaler, comprising a vaporizer device with at least one electric vaporizer for vaporizing liquid supplied to the vaporizer, at least one electrical line for an electrical voltage supply to the vaporizer, and a receptacle for retaining a replaceable liquid reservoir which is fluidically connectable to the vaporizer via an opening, wherein the receptacle comprises a device which forces the replaceable liquid reservoir with the opening into direct abutment with the vaporizer.

The present invention relates to an inhaler having the features of thepreamble of claim 1 and to a replaceable liquid reservoir for an inhalerhaving the features of the preamble of claim 7.

Such inhalers with a receptacle for a replaceable liquid reservoir areknown, for example, as electronic cigarette products.

The inhalers comprise a vaporizer device with at least one electricvaporizer for vaporizing liquid supplied to the vaporizer, at least oneelectrical line for supplying the vaporizer with electric current, and areceptacle for retaining a replaceable liquid reservoir which can befluidically connected to the vaporizer via an opening.

Conventional electronic cigarette products or inhalers comprise avaporizer device based, for example, on wick-coil technology, in whichthe liquid is transported by capillary forces from the liquid reservoiralong a wick until the liquid is heated by an electrically heatable coiland thus vaporized. The wick serves as a liquid-conducting connectionbetween the liquid reservoir and the heating coil, which serves as thevaporizer.

One disadvantage of wick-coil technology is that a lack of liquid supplyleads to local overheating, which can produce pollutants. This so-called“dry puff” must be avoided. In addition, such vaporizer devices areoften leaky due to the manufacturing process, so that liquid can escapein undesirable ways, for example via the air supply and/or vapordischarge.

To avoid the problems of wick-coil technology, DE 10 2017 111 119 A1describes a vaporizer device with a vaporizer in which liquid istransported from the liquid reservoir by a wick structure to an inletside of the vaporizer by capillary forces. The vaporizer vaporizes theliquid, and the vaporized liquid can be added to an air stream as avapor and/or aerosol. The vaporizer is electrically connectable to anenergy storage device via an electrical line for the supply ofelectrical energy.

In this context, the invention is based on the task of providing aninhaler and a replaceable liquid reservoir for an inhaler, in whichunintentional escape of the liquid is reliably prevented, or is reducedto the lowest possible level.

The invention solves the task with the features of the independentclaims.

According to claim 1, for solving the task an inhaler comprising avaporizer device with at least one electric vaporizer for vaporizingliquid supplied to the vaporizer, at least one electrical line to anelectrical voltage supply of the vaporizer, and a receptacle forretaining a replaceable liquid reservoir, which is fluidicallyconnectable to the vaporizer via an opening, is proposed, whereinaccording to the basic idea of the invention it is proposed that thereceptacle comprises means which force the replaceable liquid reservoirwith the opening into direct abutment with the vaporizer.

With the proposed solution, the liquid reservoir with the opening is indirect contact with the vaporizer without a formation of a gap, and theliquid inevitably exits through the vaporizer when exiting the liquidreservoir. Further, when the liquid exits, the liquid is directlyvaporized in the vaporizer, so that the vaporization is realized with avery good overall efficiency and the lowest possible losses.

It is further proposed that a seal sealing the opening to the outside isprovided between the vaporizer and the liquid reservoir. The providedseal can further reduce the likelihood of accidental leakage of theliquid from the vaporizer device without passing through the vaporizerin the process. In this regard, the seal encloses the contact areabetween the vaporizer device and the opening of the liquid reservoirthrough which the liquid passes from the liquid reservoir into thevaporizer device, such that the seal prevents lateral escape of theliquid or vapor at the surface from the vaporizer device. In thisregard, the seal may be provided on both the liquid reservoir and thevaporizer. However, an arrangement on the liquid reservoir has theadvantage that it is immediately replaced with a new seal when theliquid reservoir is changed.

In this context, the device can preferably comprise a clamping deviceactuated by magnetic force, which enables reversible release andreplacement of the liquid reservoir, in particular without the use of atool.

Further, the device may alternatively or also additionally comprise aspring-loaded pressing piece which is spring-loaded in the directionsuch that it forces the replaceable liquid reservoir against thevaporizer.

It is further proposed that the pressing piece is spring-loaded in thedirection of an intended flow direction in the inhaler. The intendeddirection of flow is defined by the flow of air caused in the inhalerwhen the consumer draws on the mouthpiece according to the intended use,thereby creating a negative pressure in the inhaler. Due to the proposeddirection of the spring loading, it is in the same direction as thepressure gradient generated during drawing, so that the pressure forceacting between the liquid reservoir and the vaporizer during drawing canbe increased and the tendency of the liquid reservoir to detach from thevaporizer can be counteracted.

It is further proposed that the pressing piece is spring-loadedpoint-symmetrically with respect to its longitudinal axis. Due to thepoint-symmetrical spring loading, the liquid reservoir is forced againstthe vaporizer with a compressive force that is distributed as uniformlyas possible over the circumference.

Further, to solve the problem according to claim 7, a replaceable liquidreservoir for an inhaler with a hollow space, which is filled with atleast one liquid and is releasable via an opening, and a wick structurefor transporting the liquid out of the hollow space, is proposed, inwhich the opening is enclosed by a seal, and is closed via a foil bondedto the seal.

The proposed solution can reduce or prevent accidental leakage of theliquid both before the liquid reservoir is inserted into the inhaler andwhen the liquid reservoir is inserted. In this regard, the seal isspecifically used, prior to insertion, for bonding the foil sealing theopening and, in the inserted state, for sealing the contact zone betweenthe opening of the liquid reservoir and the vaporizer.

It is further proposed that the wick structure in the liquid reservoiris formed by a sponge filling at least the opening. The sponge forms awick through its capillaries, which causes the liquid to be conveyedfrom the hollow space through the opening towards the vaporizer, whereinthe sponge enables the liquid to be supplied independently of theposition and orientation of the inhaler by the regularly repeatedfilling of the capillary and the liquid to be completely emptied fromthe hollow space.

This also allows the sponge to completely fill the hollow space so thatthe liquid is stored exclusively in the capillaries. In addition, thisallows a low pressure to be applied to the sponge in the inserted statevia the abutting vaporizer, without allowing the sponge to escape intothe hollow space. Through this pressure, the liquid can again beactively sucked in similar to the principle of felt pens, wherein theliquid is safely stored in the sponge in the case that no pressure isexerted.

This exertion of pressure can be effected by drawing on the inhaler oralso by a spring-loaded receptacle in the inhaler.

Further, the sponge may preferably be flexible in itself so that it canadjust slightly to the geometry and irregularities of a mating surfacesuch as a vaporizer when inserted into a vaporizer device. This canavoid voids and improve the transfer of liquid from the liquid reservoirto, for example, a vaporizer. Furthermore, the advantageous pressuredescribed above can thereby be converted into a compression of thesponge, by which the suction and onward transport of the liquid isfurther facilitated.

It is further proposed that the sponge is thermally stable up to atemperature of 300° C. The proposed material property prevents thematerial from melting under the effect of temperature and thecapillaries from melting down. Furthermore, it can prevent components ofthe sponge from outgassing and being added to the liquid to bevaporized.

The invention is explained below on the basis of preferred embodimentswith reference to the accompanying figures. Thereby shows

FIG. 1 a schematic view of an inhaler;

FIG. 2 a perspective section through a schematic vaporizer-tank unit;

FIG. 3 a replaceable liquid reservoir as an individual part;

FIG. 4 an enlarged view of a vaporizer tank unit with a replaceableliquid reservoir.

FIG. 1 schematically shows an inhaler 10 or an electronic cigaretteproduct. The inhaler 10 comprises a housing 11 in which an air channel30 or vent is provided between at least one air inlet opening 231 and anair outlet opening 24 at a mouth end 32 of the cigarette product 10. Themouth end 32 of the inhaler 10 thereby denotes the end at which theconsumer draws for the purpose of inhalation, thereby applying anegative pressure to the inhaler 10 and generating an air flow 34 in theair channel 30.

Advantageously, the inhaler 10 comprises a base part 16 and a vaporizertank unit 20 that comprises a vaporizer device 1 having a vaporizer 60and a liquid reservoir 18, which is in particular in the form of areplaceable interchangeable cartridge. The liquid reservoir 18 can bereplaced by the user of the inhaler 10, for which purpose the inhaler 10comprises a suitable closable access opening 2. The air drawn throughthe air inlet opening 231 is directed in the air channel 30 to the atleast one vaporizer 60. The vaporizer 60 is connected or connectable tothe liquid reservoir 18, in which at least one liquid 50 is stored. Forthis purpose, a porous and/or capillary liquid-conducting wick structure19 is advantageously arranged at an inlet side 61 of the vaporizer 60.

The vaporizer 60 vaporizes liquid 50 supplied to the vaporizer 60 fromthe liquid reservoir 18 by the wick structure 19 by means of capillaryforces, and adds the vaporized liquid as an aerosol/vapor to the airstream 34 at an outlet side 64.

The electronic cigarette 10 further comprises an electrical energystorage device 14 and an electronic control device 15. The energystorage device 14 is generally disposed in the base part 16 and may be,in particular, a disposable electrochemical battery or a rechargeableelectrochemical battery, for example, a lithium-ion battery. Thevaporizer tank unit 20 is disposed between the energy storage device 14and the mouth end 32. The electronic control device 15 comprises atleast one digital data processing device, in particular microprocessorand/or microcontroller, in the base part 16 (as shown in FIG. 1) and/orin the vaporizer tank unit 20.

Advantageously, a sensor, for example a pressure sensor or a pressure orflow switch, is arranged in the housing 11, wherein the control device15 can determine, based on a sensor signal output by the sensor, that aconsumer is drawing on the mouth end 32 of the cigarette product 10 toinhale. In this case, the control device 15 controls the vaporizer 60 toadd liquid 50 from the liquid reservoir 18 as an aerosol/vapor into theair stream 34.

The at least one vaporizer 60 is arranged in a portion of the vaporizertank unit 20 facing away from the mouth end 32. This allows foreffective electrical coupling and control of the vaporizer 60,particularly with the base part 16. Advantageously, the air flow 34passes through an air channel 30 extending axially through the liquidreservoir 18 to the air outlet opening 24.

The liquid 50 stored in the liquid reservoir 18 to be dispensed is, forexample, a mixture of 1,2-propylene glycol, glycerol, water andpreferably at least one aroma (flavor) and/or at least one activeingredient, in particular nicotine. However, the indicated components ofthe liquid 50 are not mandatory. In particular, aroma and/or activeingredients, in particular nicotine, may be omitted.

FIG. 2 shows a perspective section through a schematic vaporizer tankunit 20. The vaporizer tank unit 20 comprises a block-shaped, preferablymonolithic heating body or vaporizer 60 preferably made of anelectrically conductive material, in particular a semiconductormaterial, preferably silicon. It is not necessary that the entirevaporizer 60 be made of an electrically conductive material. It may besufficient, for example, that the surface of the vaporizer 60 iselectrically conductive, for example metallically coated or preferablysuitably doped. In this case, the entire surface need not be coated; forexample, metallic or preferably non-metallic or non-metallicallylaminated metallic conductor tracks may be provided on a non-conductiveor semi-conductive base body. It is also not essential that the entirevaporizer 60 heats; for example, it may be sufficient if a section orheating layer of the vaporizer 60 heats in the region of the outlet side64. The vaporizer 60 is heated by electrical energy based on itselectrical resistance, and thus may be referred to as a resistanceheater.

Advantageously, the vaporizer 60 is provided with a plurality ofmicrochannels or fluid channels 62 that fluidly connect an inlet side 61of the vaporizer 60 to an outlet side 64 of the vaporizer 60.

The average diameter of the liquid channels 62 is preferably in therange between 5 μm and 200 μm, further preferably in the range between30 μm and 150 μm, still further preferably in the range between 50 μmand 100 μm. Due to these dimensions, a capillary effect isadvantageously created so that liquid entering a liquid channel 62 atthe inlet side 61 rises upwardly through the liquid channel 62 until theliquid channel 62 is filled with liquid. The number of liquid channels62 is preferably in the range of four to 1000. In this way, the heatinput into the liquid channels 62 can be optimized and an ensured highvaporization performance and a sufficiently large vapor outlet area canbe realized.

The liquid channels 62 are advantageously arranged in the form of anarray. The array can be in the form of a matrix with s columns and zrows, wherein s advantageously lies in the range between 2 and 50 andfurther advantageously lies in the range between 3 and 30 and/or zadvantageously lies in the range between 2 and 50 and furtheradvantageously lies in the range between 3 and 30. In this way, aneffective and easily producible arrangement of the liquid channels 62with ensured high vaporization performance can be realized.

The vaporizer tank unit 20 comprises a carrier 4 with a passage opening104 for the liquid-conducting connection of the vaporizer 60 and aliquid reservoir 18. The carrier 4 and the vaporizer 60 are componentsof a vaporizer device 1, which realizes the electrical and mechanicalconnection of the vaporizer 60. A wick structure 19 is arranged in thepassage opening 104 for supplying liquid 50 to the vaporizer 60.

The inlet side 61 of the vaporizer 60 is liquid-conductingly connectedto the liquid reservoir 18 via the wick structure 19. The wick structure19 is used to passively feed liquid 50 from the liquid reservoir 18 tothe vaporizer 60 by means of capillary forces. The wick structure 19advantageously contacts the inlet side 61 of the vaporizer 60 in aplanar manner and covers all liquid channels 62 of the vaporizer 60 onthe inlet side. On the side opposite the vaporizer 60, the wickstructure 19 is connected to the liquid reservoir 18 in aliquid-conducting manner.

An advantageous volume of the liquid reservoir 18 is in the rangebetween 0.1 ml and 5 ml, preferably between 0.5 ml and 3 ml, furtherpreferably between 0.7 ml and 2 ml or 1.5 ml.

The vaporizer tank unit 20 is preferably connected and/or connectable toa heating voltage source 71 controllable by the control device 15, whichis connected to the vaporizer 60 for an electrical voltage supply viaelectrical lines 105 a, 105 b in a contact area 131 at opposite edgesections of the vaporizer 60, so that an electrical voltage Uh generatedby the heating voltage source 71 results in a current flow through thevaporizer 60. Due to the ohmic resistance of the electrically conductivevaporizer 60, the current flow causes heating of the vaporizer 60 andtherefore vaporization of liquid contained in the liquid channels 62.Vapor/aerosol generated in this manner escapes to the outlet side 64from the liquid channels 62 and is mixed with the air flow 34. Morespecifically, upon detecting an air flow 34 through the air channel 30caused by drawing of the consumer, the control device 15 controls theheating voltage source 71, wherein the liquid contained in the liquidchannels 62 is driven out of the liquid channels 62 in the form ofvapor/aerosol by spontaneous heating.

The vaporization temperature is preferably in the range between 100° C.and 400° C., more preferably between 150° C. and 350° C., even morepreferably between 190° C. and 290° C.

Advantageously, the vaporizer 60 may be fabricated from portions of awafer having thin film layer technology which comprises a layerthickness preferably less than or equal to 1000 μm, further preferably750 μm, still further preferably less than or equal to 500 μm. Surfacesof the vaporizer 60 may advantageously be hydrophilic.

The vaporizer tank unit 20 is adjusted to dispense an amount of liquidpreferably in the range between 1 μl and 20 μl, further preferablybetween 2 μl and 10 μl, still further preferably between 3 μl and 5 μl,typically 4 μl per puff of the consumer. Preferably, the vaporizer tankunit may be adjustable with respect to the amount of liquid/vapor perpuff, i.e., from 1 s to 3 s per puff duration.

The drive frequency of the vaporizer 60 generated by the heating voltagesource 71 is generally advantageously in the range of 1 Hz to 50 kHz,preferably in the range of 30 Hz to 30 kHz, still more advantageously inthe range of 100 Hz to 25 kHz.

The vaporizer 60 is preferably based on MEMS technology, in particularsilicon, and is therefore advantageously a micro-electro-mechanicalsystem.

In FIG. 3, the liquid reservoir 18 is shown in an enlarged view as asingle component. The liquid reservoir 18 is in the form of areplaceable interchangeable cartridge and comprises a housing 6 with ahollow space 5, in which the liquid 50 is stored. The housing 6 furthercomprises an opening 25, which is encompassed by a seal 7 and is closedvia a foil 8 bonded to the seal 7. The hollow space 5 is preferablycompletely filled with a sponge. However, if the hollow space 5 is notcompletely filled with the sponge, it is at least arranged so that itcompletely fills the opening 25. The sponge comprises a plurality ofcapillaries which are filled with the liquid and thereby form the wickstructure 19 required for supplying the liquid. The sponge is preferablyinherently flexible and thermally stable up to a temperature of 300° C.

FIG. 4 shows the vaporizer tank unit 20 with the liquid reservoir 18inserted. The vaporizer tank unit 20 comprises a tubular draw member 22having an air channel 30 provided therein and a mouthpiece 26 attachedthereto. Further, the vaporizer 60 is retained in the air channel 30 ofthe draw member 22 such that the consumer draws air through thevaporizer 60 when the mouthpiece 26 is pulled in the direction of thearrow. Further, the vaporizer tank unit 20 comprises a pressing piece 21which comprises a receptacle 27 in which the liquid reservoir 18 isretained. The pressing piece 21 is pulled against the pulling piece 22by two springs 23. The two springs 23 are arranged diametrically to alongitudinal axis L of the pressing piece 21, so that the pressing piece21 is spring-loaded in cross-section point-symmetrically to itslongitudinal axis. The pressing piece is thereby spring loaded uniformlyin the direction of its longitudinal axis L toward the vaporizer 60.Here, the spring-loaded pressing piece 21 forms a device by means ofwhich the liquid reservoir 18 is pressed against the vaporizer 60.Alternatively or additionally, the pressing piece 21 could also bepressed against the vaporizer 60 by a magnetic force. The only importantaspect of the pressure applying device is that the liquid reservoir 18can be removed from the receptacle 27 and reinserted without the aid ofa tool, if possible.

The liquid reservoir 18 is sealed via the foil 8 prior to use, i.e., theliquid 50 cannot unintentionally escape or outgas from the opening 25.To use the liquid reservoir 18, the foil 8 is removed and the liquidreservoir 18 is inserted into the receptacle 27, wherein insertion canbe facilitated by stretching the springs 23 and enlarging the receptacle27. The receptacle 27 is shaped in such a way that its shape determinesthe insertion direction of the liquid reservoir 18. The liquid reservoir18 can thus only be inserted in such a way that it comes into contactwith the free opening 25 and the seal 7 on the vaporizer 60. In doingso, the sponge, due to its inherently flexible nature, allows itssurface to conform to the surface of the vaporizer 60. Furthermore, theseal 7 is also inherently flexible and is forced against the surface ofthe vaporizer 60 in a sealing manner by the exertion of pressure via thesprings 23 so that the liquid 50 cannot escape laterally from theopening 25 without passing through the vaporizer 60. The sponge that isthe wick structure 19 is lightly forced against the vaporizer 60 by thespring loading, so that reliable contact of the wick structure 19 withthe vaporizer 60 is always realized with as few voids as possible. Inaddition, this allows the sponge to be slightly compressed, assisting inthe discharge of the liquid from the capillaries and the delivery of theliquid toward the opening 25. The liquid reservoir 18 is thus in fluidcommunication with the vaporizer 60 in the inserted state, i.e., theliquid 50 can flow from the hollow space 5 of the liquid reservoir 18into the vaporizer 60 via the opening 25.

LIST OF REFERENCE SIGNS

-   1 vaporizer device-   2 access opening-   4 carrier-   5 hollow space-   6 housing-   7 seal-   8 foil-   10 inhaler-   11 housing-   14 energy storage device-   15 control device-   16 base part-   18 liquid reservoir-   19 wick structure-   20 vaporizer tank unit-   21 pressing piece-   22 pulling piece-   23 spring-   24 air outlet opening-   25 opening-   26 mouthpiece-   27 receptable-   30 air channel-   32 mouth end-   34 air flow-   50 liquid-   60 vaporizer-   61 inlet side-   62 liquid channel-   64 outlet side-   71 heating voltage source-   104 passage opening-   105 a, 105 b electrical lines-   131 contact area-   231 air inlet opening

1. An inhaler, comprising: a vaporizer device, wherein the vaporizerdevice comprises: at least one electrical vaporizer for vaporizingliquid supplied to the at least one electrical vaporizer, at least oneelectrical line connected to an electrical voltage supply of thevaporizer, and a receptacle for retaining a replaceable liquidreservoir, which is configured to fluidically connect to the at leastone electrical vaporizer via an opening, wherein the receptaclecomprises a device which forces the replaceable liquid reservoir withthe opening into direct abutment with the vaporizer.
 2. The inhaleraccording to claim 1, wherein a seal is provided between the at leastone electrical vaporizer and the replaceable liquid reservoir sealingthe opening to the outside.
 3. The inhaler according to claim 1, whereinthe device comprises a clamping device actuated by a magnetic force. 4.The inhaler according to claim 1, wherein the device comprises aspring-loaded pressing piece.
 5. The inhaler according to claim 4,wherein the spring-loaded pressing piece is spring-loaded in a directionof an intended flow direction in the inhaler.
 6. The inhaler accordingto claim 4, wherein the spring-loaded pressing piece is spring-loadedpoint-symmetrically to a longitudinal axis (L) of the spring-loadedpressing piece.
 7. A replaceable liquid reservoir for an inhalercomprising: a hollow space which is filled with at least one liquid andis releasable via an opening, and a wick structure for transporting theat least one liquid out of the hollow space, wherein the opening isenclosed by a seal, and is closed via a foil bonded to the seal.
 8. Thereplaceable liquid reservoir according to claim 7, wherein the wickstructure is formed by a sponge filling at least the opening.
 9. Thereplaceable liquid reservoir according to claim 8, wherein the spongecompletely fills the hollow space.
 10. The replaceable liquid reservoiraccording to claim 8, wherein the sponge is flexible in itself.
 11. Thereplaceable liquid reservoir according to claim 8, wherein the sponge isthermally stable up to a temperature of 300° C.